Sleep disorders is a broad term covering all health problems related to sleep. Difficulty falling asleep, waking up repeatedly during the night, feeling excessively drowsy during the day, and still feeling tired even after sleeping are all included under this term. About 10 to 20 percent of people living in Korea experience some form of sleep disorder, yet many do not receive appropriate treatment. This article walks you through the basics of sleep, the types and causes of sleep disorders, prevention tips, and how to assess your own sleep health.
What Is Sleep?
Healthy sleep is far more than simply resting. It is a complex, structured process that helps your body and mind recover from the fatigue built up during the day and strengthens higher cognitive functions such as memory. Getting an adequate amount of sleep is essential for staying healthy.
How Much Sleep Do You Need?
Individual needs vary, but 6 to 7 hours of sleep per day is generally recommended. The simplest way to judge whether you are getting enough is this: if you do not feel drowsy while sitting quietly during the day, your sleep is likely sufficient for your needs.
Recommended sleep durations by age group are as follows:
| Age Group | Recommended Sleep Duration |
|---|---|
| Preschool and primary school children | 9 hours |
| Teenagers | 8 hours |
| Adults | 7 hours 30 minutes |
Types of Sleep Disorders
Sleep disorders fall broadly into two categories.
- Nonorganic sleep disorders: These are caused by emotional or psychological factors. Examples include nightmares, sleepwalking, and nonorganic insomnia.
- Organic sleep disorders: These are caused by physical problems in the body. Examples include narcolepsy, sleep apnea, and organic insomnia.
Common Sleep Conditions
- Chronic sleep deprivation: A state in which the total amount of sleep a person gets is simply not enough, often because of a busy social or work life.
- Poor sleep quality: A state in which a person sleeps for a sufficient number of hours but never reaches deep sleep, wakes frequently, and still feels very tired in the morning.
- Insomnia: Difficulty falling asleep, repeatedly waking during the night or waking too early, and not feeling refreshed after sleep.
- Circadian rhythm sleep disorder: A disruption of the body’s internal clock that makes it hard to fall asleep at night and hard to stay awake during the day. A completely reversed day-night cycle is a typical example.
Causes of Sleep Disorders
Almost any illness or physical discomfort can interfere with sleep. The main causes are summarized below.
Physical causes
- Conditions such as asthma, joint pain, toothache, stomach pain from a gastric ulcer, and muscle pain
- Sleep-related conditions such as sleep apnea, narcolepsy, restless legs syndrome, and nocturnal muscle cramps
Psychological and lifestyle causes
- Excessive excitement, worry, and stress
- Long-term use of sleeping pills can itself lead to insomnia
- Alcohol consumption, smoking, caffeine intake, and irregular eating habits
If you are concerned about the relationship between alcohol and sleep, please also refer to Alcohol Dependence (Alcoholism): Symptoms, Treatment, and Counseling Resources.
Other causes
- Aging
How to Prevent Sleep Disorders
Even small changes to your sleep habits can make a significant difference to the quality of your sleep. Try putting the following tips into practice.
1. Build a Regular Sleep Routine
It is important to keep your wake-up time consistent whether it is a workday or a day off. Even if you went to bed late, try not to change the time you get up. Avoid napping during the day if possible, and also keep the amount of time you spend lying in bed consistent.
Forcing yourself to lie in bed when you cannot sleep actually increases your anxiety about sleep. If you have been lying down for a while and still cannot fall asleep, it is a good idea to get out of bed, do something relaxing such as reading, and then return to bed only when you feel sleepy.
2. Keep Indoor Humidity Between 50 and 60 Percent
Dry air dries out the nasal lining, which can worsen snoring or cause you to breathe through your mouth, both of which disturb sleep. Make sure there is good air circulation in your room and maintain a comfortable level of indoor humidity.
3. Block Out Light
Even small amounts of light stimulate the nerves in the eyes and reduce the secretion of melatonin, the hormone that helps you sleep. Use thick curtains to block out light completely, and consider wearing a sleep mask if needed.
It is also best to avoid the habit of checking your phone for the time when you wake up during the night. The blue light from a phone screen entering your eyes suppresses melatonin production and makes it harder to fall back asleep.
4. Try a Warm Bath or a Glass of Warm Milk
Taking a half-body bath (sitting in water up to your waist) at around 37 to 38 degrees Celsius, which is slightly above body temperature, about 2 hours before bed helps relax the body and makes it easier to fall asleep. Milk, which is rich in amino acids and calcium, can also support sleep.
On the other hand, foods high in simple sugars such as candy, chocolate, and snacks raise blood sugar quickly and can stimulate the brain, so avoid eating these before bed.
Cigarettes and caffeinated drinks such as coffee, black tea, and cola should also be avoided before sleep. While alcohol may feel like it helps you fall asleep at first, it causes you to wake more frequently in the second half of the night and worsens sleep apnea, reducing the overall quality of your sleep.
5. Watch Your Meal Size
Avoid eating within 3 hours of going to bed. Both being too full and being too hungry can prevent restful sleep. Eating protein-rich foods such as fish or meat at lunch and carbohydrate-based foods such as grains and fruit at dinner can help promote better sleep at night.
6. Avoid Intense Exercise Late at Night
Regular daily exercise is good for your health, but vigorous exercise right before bed stimulates the sympathetic nervous system and actually makes it harder to sleep. For evening exercise, gentle activities such as light stretching, calisthenics, or a short walk are ideal for releasing muscle tension without over-stimulating the body.
7. Use Your Bed Only for Sleeping
Reading, eating, or looking at your phone in bed trains your brain to think of the bed as a place for activity, making it harder to fall asleep. Keep your bed as a space used only for sleeping. A mattress and bedding that are neither too firm nor too soft tend to support better sleep.
Sleep Self-Assessment
You can measure your level of daytime sleepiness using the Epworth Sleepiness Scale (ESS), a self-assessment tool that gives you a score to check on your own. For each of the situations below, rate how likely you are to feel drowsy.
Scoring guide
| Score | Meaning |
|---|---|
| 0 | Would never feel drowsy |
| 1 | Slight chance of feeling drowsy |
| 2 | Moderate chance of feeling drowsy |
| 3 | High chance of feeling drowsy |
Self-assessment situations
| Situation | Score (0 to 3) |
|---|---|
| Sitting and reading | |
| Watching television | |
| Sitting quietly in a public place (e.g., a theater or meeting room) | |
| Riding as a passenger in a car for an hour without a break | |
| Lying down to rest in the afternoon | |
| Sitting and talking to someone | |
| Sitting quietly after lunch (without alcohol) | |
| Sitting in a car that has stopped in traffic |
Add up your scores for all situations and check your total. A total score of 10 or above may indicate daytime sleepiness, and a score of 16 or above means it is strongly recommended that you consult a sleep specialist. For a more detailed interpretation, you can visit the Samsung Seoul Hospital Sleep Clinic. Before making an appointment, please confirm the latest information by calling 1345 (the Immigration Contact Center, which provides general support for foreigners in Korea) or contacting the relevant medical institution directly.
When to See a Doctor
If your sleep problems persist for more than 2 weeks or are affecting your daily life (work, school, household responsibilities, and so on), it is a good idea to visit a specialist clinic. Many hospitals in Korea operate sleep clinics, and you can search for a sleep specialist hospital near you through the following links:
- Korean Academy of Sleep Medicine: Hospital Search
- Korean Sleep Research Society: Sleep Clinic Search
If you need support in a language other than Korean or have questions about health insurance, please contact the National Health Insurance Service (NHIS) at 1577-1000 and press 7 for the foreigners’ dedicated line. For questions about your residence status, visa, or general daily life in Korea, please contact the Immigration Contact Center at 1345.
If you are experiencing severe psychological distress due to a sleep disorder, please also refer to Suicide Prevention and Mental Health Guide for Refugees and Migrants.
Please note that the cost of medical care and available support may differ depending on your health insurance enrollment status and type of residence permit. Before visiting a hospital, we recommend confirming the latest information by calling 1345 or visiting your local Korea Immigration Service office.
Reference Links
- Samsung Seoul Hospital Sleep Clinic
- Korean Academy of Sleep Medicine: Hospital Search
- Korean Sleep Research Society
- National Health Insurance Service Customer Center (1577-1000)
- Korea Immigration Service: Immigration Contact Center (1345)